Health trauma of floods may last after waters subside

Floods don’t just wreck your house, they may also affect your long-term health.

Record heavy rains have flooded thousands of properties in southern England since December. There have been a few deaths from the storms but none from the floods.

From past events, this is to be expected. The World Health Organization reported last year that only 0.03 per cent of the 3.4 million people caught in floods in Europe in the past decade died, with the main causes being drowning, electrocution, injury, heart attack and poisoning.

Advertisement

But that could be just part of the story. “Only the immediate traumatic deaths from flooding are recorded,” says the National Flood Emergency Framework for England. “Negative effects on well-being may persist for months or even years after a flood.”

The main evidence for this comes from a study after a flood in Bristol in 1968. In the following year, death rates rose 50 per cent and hospital admissions more than doubled – but only among people who had been flooded, not unaffected neighbours. The WHO review noted similar results in studies of survivors of hurricane Katrina in the US, and the 1998 floods in Hunan, China – and not just among those most severely affected.

Yet other studies give a different picture. In an effort to confirm the Bristol finding researchers in 2011 compared maps of the 319 floods in England and Wales between 1994 and 2005 with the death records in each postcode. They found, if anything, slightly fewer deaths after floods.

However, Bettina Menne, co-editor of the WHO review, says people affected by flooding often subsequently move house, possibly to a different, less flood-prone postcode. If more of them later died than would have normally, this would muddy the data, by cutting the apparent death-rate among the flooded and boosting it among the non-flooded. There’s also the fact that people’s health overall will have improved since 1968. The problem, Menne says, is that “a study like the one in Bristol, directly comparing people we know were flooded with people who weren’t, has never been done again, anywhere”.

One way of finding out for sure would be to set up a health registry of people flooded this time, so the health of those affected can be compared with those who weren’t. Virginia Murray of Public Health England called for such a registry in January, and said a protocol for setting one up was nearly ready. But no decision to fund one has yet been taken, she says.

Still, the standard medical surveillance of people whose homes have been flooded is reassuring. “Nothing worrying is happening,” says Murray. But what happens in six months to people fleeing floodwaters these past weeks, we may never know.